1. Field of the Invention
The present invention relates to a liquid discharge apparatus for discharging liquids from nozzles.
2. Description of the Related Art
An image recording apparatus described in United States Patent Application Publication No. 2007/0146445 A1 (corresponding to Japanese Patent Application Laid-open No. 2007-176068), which is exemplified as a liquid discharge apparatus for discharging liquids from nozzles, includes an ink-jet head which is movable reciprocatively in the scanning direction and which discharges inks from the nozzles, and ink cartridges which are provided for a main body, and the ink-jet head and the ink cartridges are connected to one another by a plurality of flexible tubes, and the plurality of tubes are arranged in a state of being bent so that the plurality of tubes can follow the movement of the ink-jet head. The plurality of tubes have first ends which are connected to the ink-jet head respectively in a state of being disposed in the direction perpendicular to the vertical direction and the scanning direction. Further, the plurality of tubes are fixed in a state of being disposed in the vertical direction at predetermined fixed portions which are intermediate portions thereof and which have positions in relation to the perpendicular direction different from those of the first ends connected to the ink-jet head. Accordingly, it is possible to decrease the height of the ink-jet head as compared with a case in which the plurality of tubes are connected to the ink-jet head in a state of being disposed in the vertical direction.
As described in United States Patent Application Publication No. 2007/0146445 A1, the reaction forces, which intend to restore the plurality of tubes from the bent state to the original state, are generated in the plurality of tubes arranged in the bent state. When the plurality of tubes are fixed while being disposed in the vertical direction at the fixed portions and the plurality of tubes are connected to the ink-jet head while being disposed in the direction perpendicular to the vertical direction and the scanning direction, then the reaction forces also act in the vertical direction, because the heights of the plurality of tubes differ between the first ends and the fixed portions respectively. On the other hand, in order to realize the recording of an image on a larger recording paper sheet by using the image recording apparatus as described above, it is necessary that large amounts of the inks should be supplied to the ink-jet head. For this purpose, it is necessary to increase the diameters of the tubes.
However, when the diameter of the tube is increased, if the thickness of the tube is increased in conformity with the increase in the diameter of the tube, then the reaction force is increased corresponding thereto. It is feared that the tube may float upwardly due to the action of the reaction force exerted in the vertical direction. On the contrary, if the thickness of the tube is decreased, then the upward floating of the tube as described above can be avoided, because the reaction force is decreased. However, it is feared that the liquid contained in the tube may escape to the outside and/or the gas may enter the tube from the outside, because the thickness of the tube is small.